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<head>
    <meta charset="UTF-8">
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    <title>伪类选择器</title>
</head>
<style>
    a:link{
        color: yellow;
    }
    a:hover{
        color: teal;
    }
    a:active{
        color: black;
    }
    a:visited{
        color: red;
    }
</style>
<body>
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</body>
</html>